I don't for a few reasons. First is that I personally don't really want to go about storing them in my freezer with my own food. Another is that I'm on a student budget (yay!) and it's also less convenient. Plus there's always a slight risk when feeding whole prey (such as bones getting caught in the throat; not significant enough that I'd recommend against it, but enough that I don't see a point in switching my own cat over). It's something I might consider more readily if I was taking care of a feral cat colony or something, but my indoor housecat who's never eaten a whole dead thing in his life probably doesn't care.